Many agricultural processes require the delivery of a granular material, such as seed, fertilizer, and the like, from a bulk storage tank toward an outlet or secondary containment system. The granular material is often motivated pneumatically through a series of lines. The flow of granular material through the lines is typically classified as one of two general types; specifically, the granular material may be motivated in a dilute phase flow or in a dense phase flow. During dilute phase flow, the volume percentage of air in the line is much greater relative to the volume percentage of granular material. Alternatively, during dense phase flow the relative ratio is reversed; meaning that a greater volume percentage of granular material is motivated through the line by a lower volume percentage of air.
In certain dense phase flow applications, the bulk storage tank(s) are pressurized relative to the ambient environment to provide a motivating force to urge the granular material from the bulk storage tank through the lines. In an alternative dense phase flow application, an induction system is used to transfer the granular material from the bulk storage tank and into the pressurized dense phase delivery system. For example, the bulk storage tank is generally maintained at approximately atmospheric pressure. The granular material is mechanically extracted from the bulk storage tank into a primary containment tank. The primary containment tank is pressurized relative to the ambient environment to again provide a motivating force to urge the granular material through the lines.
Use of an induction system for dense phase flow presents three main considerations and challenges. First, in the agricultural context, any induction system (i.e., a system used to transfer the granular material from ambient or lower pressure to line or higher pressure for use by a dense phase distribution system) must be efficient because an agricultural vehicle/implement has inherent power supply limitations, be it hydraulic, pneumatic, electric, and the like. Second, most granular material is susceptible to damage caused by the transfer process. For example, the granular material (e.g., seed) may be damaged by excessive pressure, control valving, and the like as it is urged through the overall system. Third, efficient dense phase flow is aided by ensuring a continual supply of granular material. This requires that the induction system constantly supply the granular material into the dense phase distribution system at the required pressure.
In view of at least the preceding considerations, dense phase flow presents significant challenges for any dense phase induction system. Therefore, a need exists for a dense phase induction system and method that incorporates an efficient, compact, and delicate induction valve assembly tailored to effectively overcome the established challenges.